Experimental study on corroded reinforced concrete columns repaired with textile-reinforced mortar (TRM) and organic corrosion inhibitors

Reinforcement corrosion in columns is a critical durability concern, requiring effective repair strategies. This study investigated the combined effects of textile-reinforced mortars (TRMs) and organic corrosion inhibitors (OCIs) to strengthen corroded reinforced concrete (RC) columns and mitigate further degradation. Tensile tests on TRM coupons evaluated the impact of OCIs on TRM performance, and axial compression tests assessed the structural response of TRM in small-scale corroded RC columns. Additionally, half-cell potential measurements monitored post-repair corrosion in aggressive environments. The TRM systems incorporated carbon and E-glass textiles with two distinct mortar matrices containing amino alcohol and sodium gluconate-based OCIs— a novel approach to improve corrosion resistance and repair efficiency. Key parameters included the type of TRM composite, degree of corrosion, concrete strength, number of TRM layers, and exposure to chloride dry-wet cycles. The results indicated that, at a 10 % corrosion level, TRM confinement effectively enhanced the performance of corrosion-damaged columns, resulting in strength and ductility improvements of 20 %–45.5 % and 148.6 %–220.3 %, respectively. However, as corrosion levels increased, the effectiveness of TRM in restoring strength reduced. In chloride environments, TRM remained effective, with only a 13 % strength reduction. Half-cell potential measurements confirmed that TRM modified with OCIs minimised further corrosion under aggressive conditions. Notably, TRM with polymer-modified mortar matrix incorporating amino alcohol-based inhibitor and carbon textile exhibited superior performance. The findings were used to develop a technical guide for selecting TRM compositions to repair corroded structures, with particular applicability to RC elements exposed to marine or chloride-laden environments.